1. Field of the Invention
The present invention relates to a technique of making use of a computer to make up maintenance schedules for a plurality of vehicles.
2. Description of Related Art
Maintenance of vehicles includes, for example, appropriate refueling in a manner to eliminate gas shortage in running. A technique for appropriate refueling includes, for example, an on-board navigation apparatus described in JP-A-5-272983. The apparatus comprises a fuel sensor for detecting a fuel residual quantity, and when a detection value in the fuel sensor is disregarded and it is detected that a detection value (that is, a fuel residual quantity) becomes a predetermined value or less, a minimum path up to a nearest oil station is displayed on a display device.
[Patent Document 1]
JP-A-5-272983 (paragraphs 25 to 34, FIGS. 3 and 4)
In the case where the above technique is applied to, for example, an automatic operating system for a plurality of vehicles for conveying a load such as minerals and so on, the respective vehicles can be made free from gas shortage. In the above conventional technique, however, only a path to an oil station for each vehicle is displayed according to a fuel residual quantity in the vehicle, so that there is a possibility that more vehicles than a predetermined number of vehicles arrive simultaneously at the same oil station. Ordinarily, an oil station can refuel a predetermined number of vehicles at the same time, so that when vehicles not less than the predetermined number of vehicles arrive at the same time, a wasteful waiting time is generated and productivity is decreased.
Such problem is not limited to refueling but possible in other maintenance. That is, productivity is decreased in the case where running is suspended because of simultaneous maintenance for a predetermined number of vehicles or more. In this manner, the problem that productivity cannot be maintained is especially serious, for example, in the case where it is desired that an appropriate production conformed to a disposition capacity of a crusher be maintained in a mining site involving conveyance of minerals or the like by periodically conveying broken stone successively produced according to the disposition by the crusher.